From:   Harshad Shirwadkar <harshadshirwadkar@gmail.com>
To:     linux-ext4@vger.kernel.org
Cc:     tytso@mit.edu, Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Subject: [PATCH v2 4/4] ext4: update fast commit TODOs
Date:   Thu, 23 Dec 2021 12:21:40 -0800
Message-Id: <20211223202140.2061101-5-harshads@google.com>
In-Reply-To: <20211223202140.2061101-1-harshads@google.com>
References: <20211223202140.2061101-1-harshads@google.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Harshad Shirwadkar <harshadshirwadkar@gmail.com>

This series takes care of a couple of TODOs and adds new ones. Update
the TODOs section to reflect current state and future work that needs
to happen.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
---
 fs/ext4/fast_commit.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
index a37384054c9e..dd002facf6c9 100644
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -156,15 +156,13 @@
  *    fast commit recovery even if that area is invalidated by later full
  *    commits.
  *
- * 1) Make fast commit atomic updates more fine grained. Today, a fast commit
- *    eligible update must be protected within ext4_fc_start_update() and
- *    ext4_fc_stop_update(). These routines are called at much higher
- *    routines. This can be made more fine grained by combining with
- *    ext4_journal_start().
+ * 1) Fast commit's commit path locks the entire file system during fast
+ *    commit. This has significant performance penalty. Instead of that, we
+ *    should use ext4_fc_start/stop_update functions to start inode level
+ *    updates from ext4_journal_start/stop. Once we do that we can drop file
+ *    system locking during commit path.
  *
- * 2) Same above for ext4_fc_start_ineligible() and ext4_fc_stop_ineligible()
- *
- * 3) Handle more ineligible cases.
+ * 2) Handle more ineligible cases.
  */
 
 #include <trace/events/ext4.h>
-- 
2.34.1.307.g9b7440fafd-goog